Adduct of 1, 2-dibromo-3-chloropropane and thiourea



United States Patent 1 2,947,661 Patented Aug. 2, 1960 considerably inexcess of,that which will combine with thev thiourea. Thus, a ratio ofabout four moles or more 2,947,661 of 1,2-dibromo-3chloropropane to onemole of thiourea v is recommended toobtain suitable yields in the formof ADDUCT 0F A%%%% S$%R 5 a precipitate. The addition of benzene to thereaction 3 I 1 l 1 mixture also induces precipitationi Theproductisreadily Thomas Robert Hopkins and Paul Donovan Strickler;isolated by filtration. It may be washed with benzene for JohnsonCounty, Kano, assigu r 0 P l' chfmical obtaining increased purity. f'Ihe following examples'illus- Company, Kans s y, 3 P of Mlssoul'i tratethe preparation of the adduct. No Drawing. Filed Oct. 16, 1958, Ser. No.767,519 Example 1 5 Claims. (Cl. 167-22) 103.1 grams of 97% pure1,2-dibromo-3-chloropropane (equivalent to 0.424 mole of the purehalide) was added, by means of a pipette, to 83.8 grams of a thioureasatu- This invention relates to compositions of matter. More 5 ragedmethanol 9 (eqmvalent. to mole of particularly, this invention isconcerned with a novel comsnow-ea) A p {601p ltate began formmg afterabout position of matter and the use of the same as a soil fumialf0f.the 12 d1brn'3'chloropmpane had been added The mixture was stirredand 12.3 grams of the adduct gant and as a plant food source.

1,2 dibmm ompmpane is known to be a nema removed by filtration. Theadduct wasthen washed wlth tocide and is used commercially for thispurpose. This 200 of benzene and an dljled to yleld grains of chemical,however, is a volatile liquid with a high vapor pure adduct a f onlthemm) of moles of thlouie-a pressure" It is also corrosive and quite toxiaBecause per mole of the hahde 1n the adduct, 4.2 of the hahde of thesecharacteristics it is diflicult to transport and repFeSem was adducted'The Rmduct was Isolated by i l quires especial care in utilization. Whatis needed is a g W i p from s filtrate which novel composition havingthe nematocidal activity of 22 urmg tranon' T 18 Increase the converslon1,2-dibron1o-3-chloropropane but which is an improve to E l 2 meat oversome, if not all, of the undesirable characxamp e teristics of thissubstance. The procedure of Example 1 was followed in a series Accordingto the present invention there is provided, of runs using various moleratios of thiourea to 1,2- as a novel composition of matter, thethiourea adduct of dibromo-3-chloropropane. The adduct formed in some1,2-dibromo-3-chloropropane. This adduct when applied of the runs wasalso benzene washed. The pertinent data to soil has been found to havenematocidal activity no of these runs is reported in the following tablewhich less, and indications are that it is greater, than 1,2-dishowsthat the adduct forms with a definite ratio of bromo-3-chloropropane.thiourea to 1,2-dibromo-3-chloropropane.

Adduct Analysis Weight (NHmOs Mole Ratio, Run Satd Moles Weight MolesC3H5Br20l Unwashed Benzene Washed No. CHQOH (NHmOs oiginnol oaHflBl'flclcom o e r ams) mm) i??? (Names (NH7): cininnol ogninnol Ratio Ratio Thethiourea adduct of 1,2-dibromo-3-chloropropane is The novel adduct ofthis invention may be used in the a solid with a vapor pressure lowerthan 1,2-dibromo-3- control of plant nematodes by applying it to thesoil at chloropropane so that it is more readily handled, shipped,applications of from 10 to 100 pounds per acre. It may stored and usedthan is 1,2-dibromo-3-chloropropane. be applied both before and afterplant growth. The adduct is also more soluble in water and thus willAlthough the adduct may be applied by itself as a penetrate deeper intothe soil to reach nematodes at lower dust, it is generally advisable tofirst combine it with a depths. The adduct is also a source offertilizer because suitable dispersant or carrier. Liquid carriers maybe of its thiourea content and, accordingly, will give an employed butsolvency of the adduct is to be avoided increased plant stand. since itwould thereby revert to two separate components. The adduct is readilyproduced by bringing together Solid carriers in the form of powders andgranules are thiourea and 1,2-dibromo-3-chloropropane under liquidpreferred for facilitating distribution of the adduct. Clay reactionconditions. Since 1,2-dibromo-3-ch1oropropane is a typical carrier whichmay be used. is a liquid at room temperature it may be employed inVarious changes and modifications of the invention can excess to serveboth as the reaction medium and reactant. be made and, to the extentthat they are within the spirit It is advisable, however, to combine thereactants in a of'this invention, they are intended to be within thescope suitable organic solvent such as a lower alcohol and parof thefollowing claims. ticularly methanol. With methanol as the solvent, Whatis claimed is: thiourea may be added until the methanol is saturated 1.The adduct of thiourea and 1,2-dibromo-3-chloroand then1,2-dibromo-3-clrloropropane added in liquid form. To facilitateprecipitation of the adduct, 1,2- ;libromo-S-chloropropane should bepresent in an amount propane. 1

2. The process of forming a solid adduct of thiourea andl,2-dibromo-3-chloropropane comprising intimately combining tbiourea'and 1,2-dibromo-3-ch1oropropaneto "comprises applying the adduct ofthiour'e'zi 'and 1,2-

dibromo-3-chloropropane to soil infested with nematodes:

References Cited in the file of this patent 5 UNITED STATES PATENTSRosenstesin Q June 17, 1952 OTHER REFERENCES 3 ,10 The CaliforniaCitrograph, vol. 43', No. 9, July 1 958,

p. 328. V Agr. Chemioals, vol. 7, No. 11, November 1952, p. 39.

5. THE METHOD OF CONTROLLING PLANT NEMATODES WHICH COMPRISES APPLYINGTHE ADDUCT OF THIOUREA AND 1,2DIBROMO-3-CHLOROPROPANE TO SOIL INFESTEDWITH NEMATODES.